On Tue, Jun 07, 2022 at 10:56:01AM -0700, Linus Torvalds wrote: > I worry a bit about the insanity of the "gigantic" pages, and the > mem_map_next() games it plays, but that code is from 2008 and I really > doubt it makes any sense to keep around at least for x86. The source > of that abomination is powerpc, and I do not think that whole issue > with MAX_ORDER_NR_PAGES makes any difference on x86, at least. Oh, argh, I meant to delete mem_map_next(), and forgot. If you need to use struct page (a later message hints you don't), just use nth_page() directly. I optimised it so it's not painful except on SPARSEMEM && !SPARSEMEM_VMEMMAP back in December in commit 659508f9c936. And nobody cares about performance on SPARSEMEM && !SPARSEMEM_VMEMMAP systems.
